What is a Monoblock Pump? | How does a Monoblock Pump work?

What is Monoblock Pump?

A Monoblock pump is a single segment mechanical machine with a horizontal and end suction pump which has a partially closed or open runner. In this pump, all the rotating components are mounted on a single shaft.

The name “mono” means a single unit, and the “monoblock pump” means a pump device that strongly couples with a prime mover, such as a motor.  The significant parts of a monoblock pump are Motor assembly and Pump assembly. 

There is 3 percent energy loss for the coupling-driven set and 7 percent loss for the belt-driven set.  To stop these transmission losses, the monoblock pump installs evolved. In this pump, the pump and motor install on a single shaft. In this way, the energy transfers from the motor to the shaft has 0% energy loss. The monoblock pumps usually install near the reservoir or the well.

monoblock pump

These pumps mostly use in areas such as industrial, rural, and urban. The monoblock pumps are widely utilized in the household, industrial, and consumer applications such as mining drainage irrigation, public water supply, civil engineering, construction water supply, agriculture, and many other industrial applications. These pumps are most popular due to their excellent properties, such as ease of use, extremely high speed, and scalability.

Monoblock Pump Working Principle

The monoblock pumps have different types, and each type has a little bit different work & design than the other. The working of the monoblock pump is given below:

monoblock pump working
                 Fig: Monoblock Pump Working
  1. First of all, the pump sucks fluid from the inlet valve and sends it into the impeller eye.
  2. When the fluid reaches in the impeller area, then the impeller rotates the water axially and radially with the help of centrifugal force.
  3. As the water passes through the impeller blades, these blades increase the speed of the fluid by converting its kinetic energy.
  4. After passing through the impeller area, the water enters in the diffuser or volute casing.
  5. The diffuser transforms the speed of the fluid into the pressure energy and increases the pressure of the fluid.
  6. After this, fluid discharges from the outlet valve and pumps to the desired area.

In addition, the direction of rotation of the pump must correspond to that of the arrow, i.e., clockwise. While the pump is rotating, it must be filled with liquid to prevent it from drying out. A dry operation can lead to pump failures.

Types of Monoblock Pump

There are multiple types of monoblock pumps, but the most common types are given below:

  1. Centrifugal Monoblock Pump

  2. Agriculture Monoblock Water Pumps

  3. Submersible Pump
  4. Pressure Booster Pumps
  5. Jet Pump
  6. Self-priming Pumps

1) Centrifugal Monoblock Pump

Main article: Centrifugal Pump 

These pumps mainly utilize for fresh water and liquids that do not chemically attack the pump parts. Due to their consistency and strength, the centrifugal monoblock pumps are chiefly utilized in civil, industrial and agriculture, applications.

The centrifugal monoblock pump allows the pump body to be dismantled without removing it from the pipeline. These types of pumps can utilize in a variety of conditions.

The versatility and wide range of these pumps make it easy for you to select the suitable model for your application. These pumps have high power efficiency and low running costs.

centrifugal monoblock pump
                  Fig: Centrifugal Monoblock Pump

The centrifugal pump has a body, impeller, outlet ports, and flanged suction in the internal design. It has a body of cast iron. The housing of the pump is incorporated with the cast iron backplate or the motor bracket.

The centrifugal monoblock pumps are used for domestic water, agriculture, water delivery to populated areas, hospitals, car washing, hotel, lawns, gardens, etc.


  • It consumes low power while produce has high operational efficiency
  • This pump has excellent suction lifting properties
  • Dynamically balanced revolving components like impeller and rotor
  • A centrifugal monoblock pump has a rigid and balanced structure
  • Retractable design for easy repairing and maintenance
  • It has a single shaft that guarantees correct alignment over time
  • This pump has a capacitor starter and a running motor
  • Chromed coated steel shaft stops rust on pump parts
  • The impeller is covered for long-lasting, accurate performance.
  • Powerful motor section
  • The pump has a sturdy handle that speeds up lifting considerably.
  • Correct handling of voltage instability

2) Agriculture Monoblock Water Pumps

These pumps are utilized to supply agricultural land with water. The agriculture monoblock water pumps mostly use by farmers to provide farmland with water for irrigation from rivers and canals.

The modern period of agricultural irrigation is closely related to sustainable energy use, water needs, the applications of experience and knowledge, and the consideration of market conditions to make sure optimal design of the irrigation application.

Agriculture Monoblock Pump

These pumps have a very smooth size and shape due that customers mostly demand these pumps. These can also use without coupling to the base plate, which makes them very useful in agriculture. Therefore, the monoblock pump is economically advantageous.

3) Submersible Pump

Main article: Submersible Pump working and types

A submersible pump is a closed motor pump that is attached closely to the pump body. This pump fully immerses in the water. It pumps the water by pushing it. It has a self-priming capability. The main advantage of this pump is that the height difference between the liquid level and the pump is significant, which prevents the pump from cavitation problems.

submersible pumps

This type of monoblock pump pushes the water in the surface directed instead of pulling it as jet pump do. Compared to jet pumps, these are more resourceful. They have many features such as low cost and environmental-friendly. These are primarily used as a profitable agricultural irrigation method.


  • Low cost
  • Environmental-friendly

4) Pressure Booster Pumps

The pressure booster pump is a type of pump that increases the pressure of the working fluid. These pumps can utilize for liquids or gases, but the structure varies from liquid to liquid. A gas booster works like a gas compressor.

booster pumps
                          Fig: Pressure Booster Pump

These are used to amplify gas pressure that is already greater than the ambient pressure. Pressure booster pumps are mainly used to deliver strong gas, increase gas pressure, and inflate gas cylinders.


  • Booster pump increases the liquid pressure in the system to increase the fluid flow
  • These pumps have the capability to pump fluid for applications such as manufacturing complexes and high-rise buildings etc.
  • It increases the supply of normal water
  • These pumps have a small and easy design
  • These are easy to transport

5) Jet Pump

Main article: Jet Pump working

A jet monoblock pump uses to pump water from high depths such as deeper lakes and wells to the surface of the ground. These pumps pull the fluid instead of pushing it like a submersible pump. For a good maintenance, the parts of the pump are made of stainless steel and bronze (also called the cast iron impeller). The bronze assembly blocks the continuous flow of water and heat load, achieving stable, accurate performance with no problem.

These pumps further divide into two types:

  1. Single-stage pump
  2. Double-stage pump

The single-stage jet pump has a delivery head that differs in 12, 18, and 27 ranges. In contrast, the two-stage jet pump has a delivery head of 15, 22, and 24.

These pumps use for apartments, hotels, upstairs tanks, large buildings, and domestic applications.


  • This pump has a long service life
  • Its maintenance needs low cost
  • Can handle large GLR
  • It has an efficient working

6) Self-priming Monoblock Pump

A pump that utilizes air-water composition to attain a complete primed pumping range is called a self-priming monoblock pump. Self-priming pumps are specially manufactured to re-prime water under lifting conditions.

self-priming pumps
              Fig: Self-priming Pump

These pumps are equipped with a superior “fattened belly” spiral housing, which can hold a small amount of water even when the suction tube is empty so that it can be lifted. It also includes a deflector non-return valve built into the pump inlet port.


  • Appropriate for pumping up to a head of 43m
  • Self-priming monoblock pumps can handle many liquids
  • It has a delivery ability of up to 60 lpm
  • Built-in suction filter to prevent foreign objects from entering
  • Designed for 180-240 volt wide-voltage, single-phase operation
  • Brass impeller
  • Good suction lifting properties
  • Dynamically balanced spinning components that minimize vibrations
  • The motor of this pump has class “B” insulation
  • Built-in thermal overload protector for all single-phase pumps
  • This pump has the self-priming capability

Operating Parameters of Monoblock Pumps

The working parameters of the monoblock pump vary according to the pump type. The below-given parameters are for the centrifugal monoblock pump.

  • The power range is 0.50-2.00 HP.
  • It has mechanical sealing.
  • The suction life with self-priming capacity will be 6 m
  • This pump has a 2800 rpm speed.
  • The range of the whole head range is 5-25 m.
  • This pump has a size of 25X25, 40X40, 50X50, 65X65, and 75X75.
  • It has a discharge rate of 27-900 lpm 

Components of Monoblock Pump

The components that are in this pump are:

  1. Impeller
  2. Impeller blades
  3. Inlet valve
  4. Outlet valve

1) Impeller

The impeller is a rotating component of the monoblock pump that uses centrifugal force to move the fluid axially and radially.

2) Impeller Blades

The blades of the impeller rotate with the rotation of the impeller. When the fluid strikes these blades then the blades increase the speed of the fluid.

3) Inlet Valve

An inlet valve uses to suck the fluid into the eye of the pump impeller.

4) Outlet Valve

An outlet valve uses to discharge the fluid. 

How to Choose a Monoblock Pump 

Following are some factors that you should keep in mind for the selection of the monoblock pump:

1) Household pump head

This is the height at which the pump can transfer water. You should choose the best model for your house according to the size and number of floors in the house—the height measures in feet or meters.

2) Inlet and outlet size of the household pump

This is the diameter of the inlet and outlet pipes which must correspond to the size of the incoming water supply pipe and the pipe connected to the storage tank.

3) Exit rate

This is a measure of the water pumped in one minute. For large areas, a pump with a large delivery capacity is required. So, before selecting your pump, you must check the area where you want to pump water.

4) Structure material

This factor does not disturb the application or performance of the pump, but if you are looking for a product with long service life, you must choose a pump with a brass impeller and CI motor housing.  

Advantages and Disadvantages of the Monoblock Pump

Monoblock pump has a compact and
straightforward design
It needs initial manual priming for operation
It has efficient working that increases the pump performance.This pump needs a fluid reservoir due to that the size of the pump becomes larger than other types of pumps.
Easy replacement of pump devices
It produces low vibration and noise
These have self-priming capability
Easy maintenance
It has no base plate or guards
These pumps don’t need additional base plates and coupling for fitting.
It has an easy installation
It is cost-effective

Applications of Monoblock Pumps

Monoblock pump has the following major applications:

  • These pumps use for domestic applications such as agriculture, hotels, hospitals, small farms, bungalows, apartments, gardens, and farm-houses.
  • Use for dripping and lifting purposes.
  • These pumps mostly use for civil, industrial, and agriculture applications because of their strength and consistency.
  • The centrifugal monoblock pump uses for freshwater and liquids that do not chemically attack the pump parts.
  • These use for dewatering platforms and coal fields

FAQ Section

What is the meaning of the monoblock pump?

The name “mono” means a single unit, and the “monoblock pump” means a pump device that strongly couples with a prime mover, such as a motor.

What is the difference between a monoblock pump and the centrifugal pump?

The major difference between a centrifugal pump and a monoblock pump is given below:

  • A centrifugal pump has a larger size compared to a monoblock pump
  • The centrifugal pumps have impellers and couplings, while the monoblock pumps have no coupling and base plates
  • The centrifugal pumps have a high cost than monoblock pumps
  • A centrifugal pump has a centrifugal switch, while a monoblock pump doesn’t have.

What is a self-priming pump?

The pump, which has a water jet or side channel, is known as a self-priming pump.

What is a self-priming monoblock pump?

A pump that uses air-water composition to attain a complete primed pumping range is called a self-priming monoblock pump.

See also:

1) Different Types of Pumps

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